Equipment malfunctions can occur when one or more components are misaligned. An example of equipment that is susceptible to the misalignment malfunctions is a semiconductor device test system. A type of misalignment that effects semiconductor device test systems is planar misalignment between a device under test (e.g., a die on a semiconductor wafer) and a probe card (or probe needles on a probe card).
This planar misalignment between a device under test and a probe card can cause several types of malfunctions. One example of a malfunction caused by planar misalignment is that a partial touchdown of the probe needles of a probe card can result in a tester system reading false failures for devices under test. Another example of malfunction caused by planar misalignment is that over-compression can result in damage to bonding pads, bent probe needles, or damage to adjacent electronics (when the over-compression results in probe needles extending beyond the area of probe pads). These examples of malfunction introduce error into present testing procedures, and (without a solution) limit the ability to test smaller devices having smaller pad pitches.
In the current state of the art, adjustments for planar error are made by partially disassembling a test system and manually adjusting one or more screws until planar error is reduced for a particular device under test and one particular probe card. Not only is this technique time consuming, it does not account for planar error introduced over time during the test of a wafer, it does not account for planar errors that arise over changes in temperature (during operations), and it relies on the steadiness of a person's hand to set one or more screws to a proper height even though the adjustment demands micrometer precision.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications and variations thereof will be apparent to those skilled in the art.